Form for concrete construction



2 SHEETS-SHEET l.

Patented J une 22, 1920.

J. H. CRESMER.

FORM FOR CONCRETE CONSTRUCTION.

APPLICATION FILED NOV. 1, 1919. 1,344,115.

4 1770621157: J5/z17 E Ores 7e)"; A 1' urac J. H. C-RESMERl FORM FORCONCRETE CONSTRUCTION.

APPLICATION FILED NOV-1,19lfi,

PatentedJune 22, 1920.

2 SHEETS-SHEET 2.

\ H NIH l HIHI 1512 W A L 6577 67 Q4 w v 7 W- UNITED STATES JOHN H.CRESMER, or RIVERSIDE, CALIFORNIA.

roan roa condemn CONSTRUCTION.

Specification of Letters Patent.

Application filed lt ovember 1. 1919. Serial No. 335.076.

To all whom it may concern:

Be it known that'I JOHN H. CREsMnR, a

citizen of the United t-ate's,residing at Riv ers'ide, in the county ofRiverside and State of California, have invented a new and use ful Formfor Concrete Construction, of which the following is a specification.

. This invention relates to forms for concrete construction and moreparticularly to collapsible forms which are adapted for use in buildinghollow or chambered. walls.

The object of the invention is to provide a collapsible form or corethat can be expanded or contracted uniforinl throughout its length sothat it can be readi y freed from the walls of the hole when it isdesired to remove the core from the wall.

Another object is to provide a collapsible I form constructed of rigidsections andto provide mechanism for expanding the form and which cannotbe displaced by transverse crushing strains. U

Various other objects and advantages will be apparent from the followingdetailed description of theacompanying drawings which form a part ofthis disclosure and which'illustrate a preferred form of embodiment ofthe invention.

Ofthe drawings:

Figure 1 is aside elevation of my improved form with one of the sideplates re moved to disclose the interior mechanism,

the parts being illustrated in expanded position. '7 V Fig. 2 is asimilar view with one of the es and its companion wedge shoe side platremoved,- the parts being illustrated in collapsible position.

Fig. 3 is a section on line ar -a: of Fig. 1. Fig. 4 is a section online w-'w* of Fig. 2. Fig. 5 is a side elevation ofone ofthe side platesand its companion wedge shoe.

Fig. 6 is aplan view. Fig. 7 is a section on line cl-w" of Fig.- 1. Fig.8 is a section on line av -m of Fig. 2. Fig. 9 is a perspective View ofthe wedge element comprising the wedge slide "and wedge blocks.

The form herein illustrated and described is intended for use as a corefor the formae tion ofvertical chambers in a concrete wall and in use itis positioned within the wall space intermediate the opposed exteriorwall forms. The core, when so positioned, is in an expanded conditionand when the wall is in partly set condition so as to retain its moldedcontour, the core will be collapsed for removal or for shifting to ahigher elevation for a continued molding operation.

As illustrated, the form consists of two opposed parallel side plates1-2 andtwo op- Patented June 22,1920.

posed parallel edge strips 3-4 each posi- I tioned intermediate theadjacent vertical edges of the plates 1-2 as shown in Figs. 6, 7, and 8,each edge strip havinga flat inner surface and a semicircular outersurface I having a facing 5 of sheet metal. The side plates 1-2 haveangularly inturned vertical edges which overlap the edge strips 3-4 andengage the semi-circular surfaces thereof. The top and bottom edges ofthe side plates are flanged inwardly and are reinforced by blocks 6-6and 7-7.

Each side plate is further reinforced by wedge shoes 8-9 and by aconnecting guide bar 10, all of which are secured to the respective sideplate to form an integral unit. The shoes and guide bar of each sideplate are relatively alined with those of the opposed side plate, theshoes providin-g opposed angled wedge surfaces 11-11 and 12-12 and theguide bars having opposed vertical grooves 13-13 out in their innersurfaces.

The ends of each of the wedge shoes are provided with transverseorifices 1 1 -14, the orifices of each wedge shoe beingaxially alinedtive wedge shoes by rectangular plates 16,

threaded through the last coils of the springs and engaging shouldersformed by enlarged portions of the orifices. (See Figs.- 1 and 7). Thesesprings tend to draw the two side plates together in collapsingposition.

Centrally positioned between the side plates 1-2 I provide a verticalslide 20 having vertical keys 21-21 projecting laterally from oppositesides of the slide and engaging into the grooves 13-13 of the guide bars10 of the side plates. Secured near the ends of the 'slide 20 are wedgeblocks 22-23, the block 22 being'positioned to engage between the wedgesurfaces 11-11 of the wedge shoes 8-8 andth'e block 23 being positionedto engage between the wedge surfaces 12-12 of the wedge shoes 9-9 (seeFigs. 34).

From -the above it will be evident that when the slide 20 is elevated,the wedge blocks 2223 engaging against the wedge surfaces of the wedgeshoes, will cause the side plates to be separated to expand the form.

Attached to the inner surfaces of the edge strips 3- 1 and at oppositeends thereof 1' provide brackets 2526 and pivotally connected to saidbrackets and to the opposite ends of the slide 20 are pairs of togglelinks 2T2S. (Sec Figs. l-Q). With the form in collapsed condition asshown in Fig. 2, it

"will be understood that an upward movement oi the slide 20 will tend tostraighten the toggle links to the dead-center position shown in Fig. land by such movement will separate the edge strips in a form expandingoperation.

The means for translating the slide 9A comprises a hand lever 30 havinga pivot pin 31 journaled in the reinforcing blocks G-G of the sideplates and which is connected to the slide by a connecting link 32. Viththe form in collapsed condition as shown in Fig. 2, a turning oi thehand lever 30 in a counter-clockwise direction will elevate the slide toexpand the term, the parts then assuming the positions shown in Fig. '1,after which a flanged cover 33, having a slot for the passage of thehand lever, is placed over the top of theform, a rod 34: being threadedthrough an orifice in the hand lever above the cover and extended beyondthe sides of the form to provide a means by whichthe form can besuspended from any suitable support.

It will be evident that as the toggle links 27-28 are straightened todead-center position in a form expanding operation, the edge strips 3etwill. be maintained in expanded position against all transverse crushingstrains so long as the slide 20 is maintained in elevated position.

It 7 will be noted that the cooperating wedge surfaces of the wedgeblocks 22-23 and wedge shoes 8-9 of each side plate are correspondinglyangled to a'degree not exceeding the angle of repose, the angle ofrepose beingS degrees plus a co-eificient of friction. Therefore,regardless of the-transverse crushing strains which may be applied tothe side plates, the wedge surfaces will exert no camming influence uponthe slide 20 such as would tend to force it downwardly to collapsingposition.

From the above it will be understood that the operating mechanism cannotbe displaced by transverse crushing strains applied to the form and thatthe means formed by the cover for maintaining the hand lever in operatedposition, is only to prevent an accidental displacement thereof.

In using the form in the construction of a wall the concrete is broughtto a level flush with the upper surface of the cover; the downwardlyprojecting flange of the cover wedge shoes forming a groove in the topsurface of the wall section being molded, and when the form is elevatedfor the melding of the next higher wall section, the concrete will enterthe groove in the first section to form a tongue and groove jointbetween the sections.

I claim:

1. Adevice of the class described having opposed side'plates providedwith angled wedge shoes, edge strips intermediate the side plates, avertically movable slide intermediate the side plates and edge stripsand provided with wedge blocks adapted to cooperate with the adjacentwedge shoes, toggle-links pivotally. connected to the edge strips and tothe slide, means for translating the slide, and means yieldingly urgingthe side plates toward each other.

2. A device of the class described having opposed side plates providedwith angled and vertical guide grooves, edge strips intermediate theside plates, a vertically movable slide having keys engaging into. theguide grooves, wedge blocks carried by the slide in position forcooperation with the wedge shoes, toggle links pivotally connected tothe edge strips and to the slide, n'icans for translating the slide, andmeans yicldingly urging the side plates toward each other. l

3. A device of the class described having opposed side plates eachformed with inturned i edges and provided with spaced wedge shoes, edgestrips intermediate the inturned edges of the side plates, aslide havingspaced wedge blocks positioned for cooperation with the companion wedgeshoes of the side plates, toggle-links pivotally connected to the edgestrips and to the slide, means for translating theslide, and meansyieldingly urgingthe side plates toward each other.

4,. A device of the class described having opposed parallel side platesformed with angled wedge shoes, the shoes of one plate being oppositelydisposed relative to those of the other plate, parallel edge stripsintermediate the side plates and oppositely positioned adjacent theedges thereof, a slide intermediate the side plates and having wedgeblocks adapted to engage between the wedge shoes to separate the sideplates, toggle'links pivotally connected to the edge strips and to theslide, means for translating the slide,and means yieldingly urging theside plates toward each other.

A device of the class described having opposed side plates provided withangled wedge shoes, edge strips intermediate the side plates, avertically movable slide intermediate the side plates and edge stripsand provided with wedge blocks adapted to cooperate with the adjacentwedge shoes, toggle-links pivotally connected to the. edge strips and tothe slide, means for translating the slide, means yieldingly urging theside plates toward each other, and a cover element maintaining the slidetranslating means in operated position.

6. A device of the class described having opposed side plates providedwith angled wedge shoes and vertical guide grooves, edge stripsintermediate the side plates, avertically movable slide having keysengaging into the guide grooves, wedge blocks carried by the slide inposition for cooperation with the wedge shoes, toggle links pivotallyconnected to the edge strips and to the slide, means for translating theslide, means yieldingly urging the side plates toward each 'other, and acover element maintaining the slide translating means in operatedposition.

7. A device of the class described having opposed side plates eachformed with inturned edges and provided with spaced wedge shoes, edgestriips intermediate the inturned edges of the side plates, a slidehaving spaced wedge blocks positioned for cooperation wlth the companionwedge shoes of the side plates, toggle-links pivotally connected to theedge strips and to the slide, means for translating the slide, meansyieldingly urging the side plates toward each other, and a cover elementmaintaining the slide translating means in operated position.

8. ,A device of the class described having opposed parallel side platesformed with angled wedge shoes, the shoes of one plate being oppositelydisposedrelative to those Signed at Riverside, California, this 16th dayof October, 1919.

JOHN H. CRESMER.

Witnesses:

CLARENCE B. FOSTER, L. BELLE WEAVER.

